1. Field of the Invention
The present invention relates to dust filtering and collection apparatuses and, more particularly, is directed to dust collection apparatus for collecting and filtering dust created by a mining machine.
2. Description of the Invention Backgound
Over the years, many different methods and apparatuses have been developed to extract coal and other valuable materials from beneath the earth's surface. Today, a variety of automated equipment exists for mining such materials at great subterranean depths.
One type of coal mining apparatus comprises a mobile mining machine that has a rotatable cutting or mining head that is equipped with a plurality of cutting bits adapted to dislodge the coal from the seam. The cutting head is typically attached to a movable boom arrangement that enables the position of the cutting head to be adjusted relative to the mine floor. As the cutting head is rotated and advanced into the seam, the coal is dislodged from the mine face and is received on gathering and conveying apparatuses mounted to the mining machine. The conveying apparatus discharges the mined coal onto separate freestanding or mobile conveying apparatus for eventual transfer out of the mine.
As the cutting bits engage the coal, fine particles of dust are created which, if not controlled, tend to permeate the air around the mining machine. Many methods and apparatuses have been developed in an effort to control the proliferation of such dust throughout the mine. For example, temporary barriers are typically used to direct fresh air across the mine face and into an exit duct arrangement wherein the dust laden air can be filtered. In addition, various mining machine-mounted filter/duct arrangements have also been used to filter dust laden air at the mine face.
For example, U.S. Pat. No. 3,387,889 to Ziemba et al. discloses a coal dust removal and conveyance system for use in connection with a continuous mining machine that comprises a duct-like air flow chamber that is attached to the mining machine boom for travel therewith. The air flow chamber has openings therein that are adjacent to the mining machine's cutter heads to permit dust laden air to be drawn into the air flow chamber. The rear portion of the air flow chamber is attached to a filter tank by a flexible coupling member which allows the air flow member to pivotally travel with the boom. A blower is operably coupled to the filter tank for drawing the dust laden air into the air flow chamber and through the filter tank. The blower is rigidly attached to the mining machine, while the filter member can be pivotally supported on the mining machine to enable it to be selectively tilted toward and away from the blower.
Another mine dust collection apparatus for use in connection with a continuous miner is disclosed in U.S. Pat. No. 3,712,678 to Amoroso. This apparatus has a first duct housing that is mounted to the mining machine boom for travel therewith. A second duct housing is rigidly mounted to the mining machine's chassis. A third connecting duct housing overlies the adjacent ends of the first and second ducts. The connecting duct housing is pivotally mounted to the second duct housing to permit the first duct housing to pivot with the boom.
U.S. Pat. No. 3,743,356 to Sheets discloses a coal dust removal system for use with a mining machine that comprises a forward hood member that is pivotally attached to an enclosure hood that houses a filter chamber and a fan chamber. The forward hood member is pivotally attached to the enclosure hood such that it can pivotally travel with the boom of the mining machine. The enclosure hood is fixed to the main frame member of the mining machine.
The above-discussed duct arrangements and others like them comprise heavy, rigid structures that are fitted onto the mining machine to clean contaminates at the mine face. Because such ductwork is typically attached to the top of the mining machine and generally extends the entire length thereof, access to the mining machine components located under such ductwork is limited. Thus, typical ductwork arrangements often must be completely removed from the mining machine by auxiliary equipment to enable one to gain access to the components located thereunder. Such removal processes are difficult to perform in the confines of the mine and are usually very time consuming. Many unproductive hours can be wasted in the process of removing the ductwork to gain access to an otherwise readily repairable hose leak located under the ductwork.
U.S. Pat. No. 5,597,393 discloses a displaceable filtering apparatus that, in many cases, effectively addresses the above-mentioned problems. The filtering apparatus disclosed in that patent is pivotally attached to mining machine frame to enable the apparatus to be selectively pivoted to a position which exposes the components located thereunder. Unfortunately, in applications wherein the seam is rather short in height, often times there is not enough head room to accommodate the pivotally displaced duct assembly.
Accordingly, there is a need for a ductwork system for use in connection with a mining machine that can remove airborne contaminates from the mine face and can be easily maneuvered and manipulated to provide quick access to the various components of the mining machine or other vehicle to which it is attached in applications where ceiling height may be limited.